/*
* linux/drivers/char/selection.c
*
* This module exports the functions:
*
* 'int set_selection(const unsigned long arg)'
* 'void clear_selection(void)'
* 'int paste_selection(struct tty_struct *tty)'
* 'int sel_loadlut(const unsigned long arg)'
*
* Now that /dev/vcs exists, most of this can disappear again.
*/
#include <linux/tty.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/malloc.h>
#include <linux/types.h>
#include <asm/segment.h>
#include "vt_kern.h"
#include "consolemap.h"
#include "selection.h"
#ifndef MIN
#define MIN(a,b) ((a) < (b) ? (a) : (b))
#endif
/* Don't take this from <ctype.h>: 011-015 on the screen aren't spaces */
#define isspace(c) ((c) == ' ')
/* Variables for selection control. */
/* Use a dynamic buffer, instead of static (Dec 1994) */
int sel_cons = 0; /* must not be disallocated */
static volatile int sel_start = -1; /* cleared by clear_selection */
static int sel_end;
static int sel_buffer_lth = 0;
static char *sel_buffer = NULL;
#define sel_pos(n) inverse_translate(scrw2glyph(screen_word(sel_cons, n, 1)))
/* clear_selection, highlight and highlight_pointer can be called
from interrupt (via scrollback/front) */
/* set reverse video on characters s-e of console with selection. */
inline static void
highlight(const int s, const int e) {
invert_screen(sel_cons, s, e-s+2, 1);
}
/* use complementary color to show the pointer */
inline static void
highlight_pointer(const int where) {
complement_pos(sel_cons, where);
}
/* remove the current selection highlight, if any,
from the console holding the selection. */
void
clear_selection(void) {
highlight_pointer(-1); /* hide the pointer */
if (sel_start != -1) {
highlight(sel_start, sel_end);
sel_start = -1;
}
}
/*
* User settable table: what characters are to be considered alphabetic?
* 256 bits
*/
static u32 inwordLut[8]={
0x00000000, /* control chars */
0x03FF0000, /* digits */
0x87FFFFFE, /* uppercase and '_' */
0x07FFFFFE, /* lowercase */
0x00000000,
0x00000000,
0xFF7FFFFF, /* latin-1 accented letters, not multiplication sign */
0xFF7FFFFF /* latin-1 accented letters, not division sign */
};
static inline int inword(const unsigned char c) {
return ( inwordLut[c>>5] >> (c & 0x1F) ) & 1;
}
/* set inwordLut contents. Invoked by ioctl(). */
int sel_loadlut(const unsigned long arg)
{
int i = verify_area(VERIFY_READ, (char *) arg, 36);
if (i)
return i;
memcpy_fromfs(inwordLut, (u32 *)(arg+4), 32);
return 0;
}
/* does screen address p correspond to character at LH/RH edge of screen? */
static inline int atedge(const int p)
{
return (!(p % video_size_row) || !((p + 2) % video_size_row));
}
/* constrain v such that v <= u */
static inline unsigned short limit(const unsigned short v, const unsigned short u)
{
/* gcc miscompiles the ?: operator, so don't use it.. */
if (v > u)
return u;
return v;
}
/* set the current selection. Invoked by ioctl() or by kernel code. */
int set_selection(const unsigned long arg, struct tty_struct *tty, int user)
{
int sel_mode, new_sel_start, new_sel_end, spc;
char *bp, *obp;
int i, ps, pe;
do_unblank_screen();
{ unsigned short *args, xs, ys, xe, ye;
args = (unsigned short *)(arg + 1);
if (user) {
int err;
err = verify_area(VERIFY_READ, args, sizeof(short) * 5);
if (err)
return err;
xs = get_user(args++) - 1;
ys = get_user(args++) - 1;
xe = get_user(args++) - 1;
ye = get_user(args++) - 1;
sel_mode = get_user(args);
} else {
xs = *(args++) - 1; /* set selection from kernel */
ys = *(args++) - 1;
xe = *(args++) - 1;
ye = *(args++) - 1;
sel_mode = *args;
}
xs = limit(xs, video_num_columns - 1);
ys = limit(ys, video_num_lines - 1);
xe = limit(xe, video_num_columns - 1);
ye = limit(ye, video_num_lines - 1);
ps = ys * video_size_row + (xs << 1);
pe = ye * video_size_row + (xe << 1);
if (sel_mode == 4) {
/* useful for screendump without selection highlights */
clear_selection();
return 0;
}
if (mouse_reporting() && (sel_mode & 16)) {
mouse_report(tty, sel_mode & 15, xs, ys);
return 0;
}
}
if (ps > pe) /* make sel_start <= sel_end */
{
int tmp = ps;
ps = pe;
pe = tmp;
}
if (sel_cons != fg_console) {
clear_selection();
sel_cons = fg_console;
}
switch (sel_mode)
{
case 0: /* character-by-character selection */
new_sel_start = ps;
new_sel_end = pe;
break;
case 1: /* word-by-word selection */
spc = isspace(sel_pos(ps));
for (new_sel_start = ps; ; ps -= 2)
{
if ((spc && !isspace(sel_pos(ps))) ||
(!spc && !inword(sel_pos(ps))))
break;
new_sel_start = ps;
if (!(ps % video_size_row))
break;
}
spc = isspace(sel_pos(pe));
for (new_sel_end = pe; ; pe += 2)
{
if ((spc && !isspace(sel_pos(pe))) ||
(!spc && !inword(sel_pos(pe))))
break;
new_sel_end = pe;
if (!((pe + 2) % video_size_row))
break;
}
break;
case 2: /* line-by-line selection */
new_sel_start = ps - ps % video_size_row;
new_sel_end = pe + video_size_row
- pe % video_size_row - 2;
break;
case 3:
highlight_pointer(pe);
return 0;
default:
return -EINVAL;
}
/* remove the pointer */
highlight_pointer(-1);
/* select to end of line if on trailing space */
if (new_sel_end > new_sel_start &&
!atedge(new_sel_end) && isspace(sel_pos(new_sel_end))) {
for (pe = new_sel_end + 2; ; pe += 2)
if (!isspace(sel_pos(pe)) || atedge(pe))
break;
if (isspace(sel_pos(pe)))
new_sel_end = pe;
}
if (sel_start == -1) /* no current selection */
highlight(new_sel_start, new_sel_end);
else if (new_sel_start == sel_start)
{
if (new_sel_end == sel_end) /* no action required */
return 0;
else if (new_sel_end > sel_end) /* extend to right */
highlight(sel_end + 2, new_sel_end);
else /* contract from right */
highlight(new_sel_end + 2, sel_end);
}
else if (new_sel_end == sel_end)
{
if (new_sel_start < sel_start) /* extend to left */
highlight(new_sel_start, sel_start - 2);
else /* contract from left */
highlight(sel_start, new_sel_start - 2);
}
else /* some other case; start selection from scratch */
{
clear_selection();
highlight(new_sel_start, new_sel_end);
}
sel_start = new_sel_start;
sel_end = new_sel_end;
if (sel_buffer)
kfree(sel_buffer);
sel_buffer = kmalloc((sel_end-sel_start)/2+1, GFP_KERNEL);
if (!sel_buffer) {
printk("selection: kmalloc() failed\n");
clear_selection();
return -ENOMEM;
}
obp = bp = sel_buffer;
for (i = sel_start; i <= sel_end; i += 2) {
*bp = sel_pos(i);
if (!isspace(*bp++))
obp = bp;
if (! ((i + 2) % video_size_row)) {
/* strip trailing blanks from line and add newline,
unless non-space at end of line. */
if (obp != bp) {
bp = obp;
*bp++ = '\r';
}
obp = bp;
}
}
sel_buffer_lth = bp - sel_buffer;
return 0;
}
/* Insert the contents of the selection buffer into the queue of the
tty associated with the current console. Invoked by ioctl(). */
int paste_selection(struct tty_struct *tty)
{
struct wait_queue wait = { current, NULL };
char *bp = sel_buffer;
int c = sel_buffer_lth;
int l;
struct vt_struct *vt = (struct vt_struct *) tty->driver_data;
if (!bp || !c)
return 0;
do_unblank_screen();
add_wait_queue(&vt->paste_wait, &wait);
do {
current->state = TASK_INTERRUPTIBLE;
if (test_bit(TTY_THROTTLED, &tty->flags)) {
schedule();
continue;
}
l = MIN(c, tty->ldisc.receive_room(tty));
tty->ldisc.receive_buf(tty, bp, 0, l);
c -= l;
bp += l;
} while (c);
remove_wait_queue(&vt->paste_wait, &wait);
current->state = TASK_RUNNING;
return 0;
}
